1. Field of the Invention
The present invention relates to a tool holder assembly, and more particularly to a tool holder assembly incorporating an adapter configured to deliver a fluid to a cutting tool.
2. Background Art
Previously, drill chucks incorporated a fluid supply hole adapted to receive a straight shank of an oil-through-drill, as described in U.S. Pat. No. 5,649,714. In that patent, a seal block was positioned in the fluid supply hole to regulate fluid flow into a fluid channel of the oil-through-drill and into a gap portion between the fluid supply hole and the straight shank portion. Such drill chucks did not address the desirability of gap-free sealing between a cutting tool and an adapter to inhibit fluid leakage and improve tool life. Moreover, such drill chucks were not configured for use with a minimum quantity lubrication (MQL) machining system in which very limited amounts of lubricant are provided at high pressure to the cutting surfaces of the cutting tool to sustain the machining process. In addition, such chucks did not incorporate adjustment screws to facilitate the axial positioning of the cutting tool.
Before Applicants' invention, there was a need for a tool holder assembly that was compatible with an MQL machining system and facilitated the supply of pressurized fluid to the cutting surfaces of a cutting tool while inhibiting fluid leakage. In addition, there was a need to incorporate the functionality of an adjustment screw to accurately position the cutting tool without the need to manufacture, position, and install a separate adjustment screw component. Problems associated with the prior art as noted above and other problems are addressed by Applicants' invention as summarized below.